This invention relates to safety decouplers and more particularly relates to such a decoupler capable of automatically disengaging an overrunning clutch from an output shaft to avoid excessive overspeeding of the clutch through driving thereof from the output shaft in the event of failure.
Overrunning clutches are normally utilized between a starter mechanism and the drive shaft of a prime mover engine. Normally the overrunning clutch operates to deliver torque from the starter to the drive shaft for initiating rotation of the latter. Once the drive shaft speed exceeds that of the clutch, the output shaft can continue to accelerate without transmitting torque through the uni-directional clutch which would overspeed the starter. In certain instances of failure, for instance of the overrunning clutch, continued acceleration of the drive shaft can transmit torque reversely to overspeed the clutch and destroy the clutch and the starter mechanism associated therewith.
Various arrangements of prior art clutching mechanisms and/or safety devices therefor may be found in the following U.S. Pat. Nos: 2,710,763; 2,744,396; 2,942,480; 2,942,481; 2,964,931; 3,136,400; 3,153,334; and 4,061,216.